Evaluate the following expression when $a = 5$ and $b = 4$. $3$ $a$ $^2 + 6$ $b$ $ - 8$
Answer: Substitute $5$ for ${a}$ and $4$ for ${b}$ $ = 3{(5)}^2 + 6{(4)} - 8 $ Remember order of operations. Evaluate the exponent before you multiply. $ = 3(25) + 6{(4)} - 8 $ $ = 75 + 24 - 8 $ $ = 91$